JP2012097795A - Active liquid seal type vibration-proofing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active liquid seal type vibration-proofing device whose cost can be reduced by simplifying its structure and cutting down its assembling man-hour.SOLUTION: Since a piston member 9 is formed of a rubber-like elastic body, integrally with a diaphragm 7, there is no need for forming the piston member 9 and the diaphragm 7 separately from each other and couple both the parts by a caulking process as conventional ones. Accordingly, the assembling man-hour is cut down to enable the product cost to be reduced. Further, comparing with the case where the piston member 9 is made of a resin material, the material cost can be reduced, permitting the product cost to be reduced by just that much.

Description

  The present invention relates to an active liquid-filled vibration isolator, and more particularly to an active liquid-filled vibration isolator that can reduce product cost by simplifying the structure and reducing the number of assembly steps. is there.

  2. Description of the Related Art There is known an active liquid-filled vibration isolator that generates a vibration force having a period corresponding to the frequency of vibration to be vibration-isolated by using an actuator driving force to actively reduce vibration. For example, Patent Document 1 discloses an active liquid-filled vibration isolator that vibrates the vibration plate 112 in the pressure receiving chambers 42 and 48 using the driving force of the electromagnetic actuator 68.

  The active liquid-filled vibration isolator disclosed in Patent Document 1 includes a first mounting bracket 12 attached to the engine side and a second mounting bracket 14 attached to the vehicle body side by a main rubber elastic body 16. A liquid sealing chamber is formed between the diaphragm 26 connected to the second mounting bracket 14 and the main rubber elastic body 16, and the liquid sealing chamber is separated from the pressure receiving chambers 42 and 48 by the partition bracket 40. It is partitioned from the equilibrium chamber 44. The vibration plate 112 is fitted in a through-hole 110 formed in the partitioning bracket 40, and the vibration plate 112 is vibrated in the opposite phase to the input vibration by the electromagnetic actuator 68, thereby reducing vibration. Is done.

  The diaphragm 26 is vulcanized and bonded to a coupling metal 28, and a drive rod 66 of an electromagnetic actuator 68 is screwed to the lower surface side of the coupling metal 28, and the upper surface side of the coupling metal 28 is The vibration plate 112 is fixed by caulking. In other words, the vibration plate 112 is connected to the drive rod 66 through the connection fitting 28.

Japanese Patent Laying-Open No. 2005-291276 (FIG. 1, paragraphs [0053 to 0056], etc.)

  However, in the above-described conventional active liquid-filled vibration isolator, the vibration plate 112 is fixed to the connection fitting 28 by caulking, and the vibration plate 112 and the drive rod 66 are connected via the connection fitting 28. Since the structure is connected, there is a problem that the number of assembling steps is increased and the product cost is increased accordingly.

  The present invention has been made to solve the above-described problems, and an active liquid-filled vibration isolator capable of reducing product cost by simplifying the structure and reducing the number of assembly steps. It is intended to provide.

Means for Solving the Problems and Effects of the Invention

  According to the active liquid-filled vibration isolator of the first aspect, the piston member is vibrated and displaced in the axial direction by the driving force of the actuator, so that the hydraulic pressure of the first liquid chamber is controlled. In this case, since the piston member is integrally formed with the diaphragm from the rubber-like elastic body, it is not necessary to connect these parts by caulking or the like unlike the conventional product in which the piston member and the diaphragm are formed as separate parts. . Therefore, there is an effect that the number of assembling steps can be reduced and the product cost can be reduced. Further, since the material cost can be reduced as compared with the case where the piston member is made of a resin material, there is an effect that the product cost can be reduced accordingly.

  On the other hand, when the piston member is composed of a rubber-like elastic body, the piston member is elastically deformed by the hydraulic pressure received during the vibration displacement, and a force transmission loss occurs. Therefore, the generated force due to the vibration displacement of the piston member is reduced, and the hydraulic pressure control of the first liquid chamber becomes insufficient. On the other hand, according to the first aspect, since the drive shaft formed of the metal material is embedded in the piston member, the hydraulic pressure received during the vibration displacement can be received by the drive shaft. Therefore, since the transmission loss of force can be reduced and the generated force can be ensured, there is an effect that the hydraulic pressure control of the first liquid chamber can be reliably performed.

  According to the active liquid-filled vibration isolator according to claim 2, in addition to the effect exhibited by the active liquid-filled vibration isolator according to claim 1, the drive shaft has a base formed in the shape of a shaft, And a projecting portion that projects outward in the radial direction at the axial tip of the base portion, and at least a part of the base portion and the projecting portion are embedded in the piston member. There is an effect that it is possible to improve the generated force due to the vibration displacement. That is, an overhang is formed at the tip of the base in the axial direction, and the drive shaft has a T-shaped cross section, so that the area necessary for receiving the hydraulic pressure is secured and the transmission loss of force is reduced. On the other hand, by reducing the remaining portion (base) of the drive shaft that is not the portion that receives the hydraulic pressure, the weight can be reduced without affecting the generation of force transmission loss.

  According to the active-type liquid-filled vibration isolator according to claim 3, in addition to the effect exhibited by the active-type liquid-filled vibration isolator according to claim 1 or 2, while projecting from the outer peripheral surface of the piston member Since it includes a rib that extends in the circumferential direction of the piston member and is composed of a rubber-like elastic body, the hydraulic pressure is prevented from escaping from the gap between the outer peripheral surface of the piston member and the inner peripheral surface of the insertion hole, There is an effect that it is possible to improve the generated force due to the vibration displacement of the piston member. As a result, the hydraulic pressure control of the first liquid chamber can be reliably performed.

  That is, when the rib is not provided, if the outer peripheral surface of the piston member comes into contact with the insertion hole due to axial deviation or dimensional tolerance, a large driving force is required to reciprocate the piston member. It is necessary to provide a predetermined gap between the outer peripheral surface and the inner peripheral surface of the insertion hole. Therefore, the hydraulic pressure escapes from the gap, and the generated force is reduced accordingly. On the other hand, in claim 3, the clearance between the outer peripheral surface of the piston member and the inner peripheral surface of the insertion hole is left as it is, and the escape of the hydraulic pressure is suppressed by the rib to improve the generated force. Can do. Further, even if the piston member is assembled in the insertion hole in the state of being off-axis, the reciprocating displacement of the piston member can be made possible with a relatively small driving force by adapting the rib.

  Further, as described above, the rib is provided on the outer peripheral surface of the piston member, so that the rib can be used to position the piston member with respect to the insertion hole (arrangement at a position where the axial centers coincide with each other). Therefore, there is an effect that the assembling work can be simplified. That is, when a predetermined gap is provided between the piston member and the insertion hole, the piston member is assembled to the insertion hole and the piston member and the actuator are connected so that the gap is uniform in the circumferential direction. Work becomes necessary, and the work becomes complicated. On the other hand, in claim 3, the piston member can be positioned (centered) with respect to the insertion hole by inserting the piston member through the insertion hole and bringing the rib into contact with the insertion hole. In addition, the operation of connecting the piston member and the actuator can be facilitated.

  Further, since the rib is made of a rubber-like elastic body, even if the piston member is assembled at a position offset from the insertion hole, the rib is elastically deformed and absorbs the offset. It is possible to suppress the formation of a gap between the outer peripheral surface of the member and the inner peripheral surface of the insertion hole. Therefore, there is an effect that the generated pressure can be secured by suppressing the hydraulic pressure from escaping from the gap.

  According to the active liquid-filled vibration isolator according to claim 4, in addition to the effect exhibited by the active liquid-filled vibration isolator according to claim 3, the rib is formed integrally with the piston member. There is an effect that it is possible to achieve a reduction in the amount and improvement in durability. In other words, ribs can be formed at the same time as the piston member during vulcanization molding, and there is no need to prepare the ribs as separate parts or to fix the ribs to the outer peripheral surface of the piston members by bonding or the like. The number of points and assembly man-hours can be reduced to reduce the product cost, and the fixation between the piston member and the rib can be strengthened to improve the durability.

  Here, in the conventional product in which the piston member is made of a resin material, even if the rib is integrally formed from the resin material on the outer peripheral surface of the piston member, the rib cannot be brought into contact with the inner peripheral surface of the insertion hole. If this resin rib is in contact with the inner peripheral surface of the insertion hole, the frictional resistance generated between the piston member and the inner peripheral surface of the insertion hole becomes excessive when the piston member is vibrated and displaced. This is because sufficient power cannot be secured due to loss. In this case, since the ribs are not elastically deformed, the durability cannot be secured sufficiently. On the other hand, when a rib made of a rubber-like elastic body is bonded to the outer peripheral surface of the piston member made of a resin material, the reliability of the fixing strength cannot be ensured. Further, as described above, the number of parts and the number of assembly steps are increased.

  Thus, the structure which forms a rib in the outer peripheral surface of a piston member is impossible in the conventional product, and, as in claim 4, the piston member is formed of a rubber-like elastic body, and the piston member and the rib Is made possible for the first time, and this can improve the durability while improving the durability and reducing the product cost.

1 is a cross-sectional view of an active liquid-filled vibration isolator in a first embodiment of the present invention. (A) is a top view of a partition plate, (b) is sectional drawing of the partition plate in the IIb-IIb line | wire of Fig.2 (a). (A) is a top view of a diaphragm and a piston member, (b) is sectional drawing of the diaphragm and piston member in the IIIb-IIIb line | wire of Fig.3 (a). It is a partial expanded sectional view of the active liquid enclosure type vibration isolator in 2nd Embodiment. (A) is a top view of a partition plate, (b) is sectional drawing of the partition plate in the Vb-Vb line | wire of Fig.5 (a). (A) is a top view of a diaphragm and a piston member, (b) is sectional drawing of the diaphragm and piston member in the VIb-VIb line | wire of Fig.6 (a). (A) is a partial enlarged cross-sectional view of the active liquid-filled vibration isolator in a state where the piston member is maximally displaced upward, and (b) is an active type in a state where the piston member is maximally displaced downward. It is a partial expanded sectional view of a liquid enclosure type vibration isolator.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of an active liquid-filled vibration isolator 100 according to the first embodiment of the present invention. FIG. 1 shows a state before the engine is supported (that is, a state before the weight of the engine is loaded).

  This active liquid-filled vibration isolator 100 is an anti-vibration device for supporting and fixing an automobile engine so that the engine vibration is not transmitted to the vehicle body frame. As shown in FIG. A first mounting bracket 1 that is attached to the vehicle body, a cylindrical second mounting bracket 2 that is mounted on the vehicle body frame side below the engine, a vibration isolating base 3 that is connected to the first mounting bracket 1 and is formed of a rubber-like elastic body, and a second A liquid sealing chamber 8 is formed between the mounting bracket 2 and the vibration isolating base 3, and a diaphragm 7 made of a rubber-like elastic body, and a drive shaft 23 connected to the diaphragm 7 and made of a metal material. The actuator 20 is disposed on the opposite side of the liquid sealing chamber 8 with the diaphragm 7 interposed therebetween, and is displaced in the axial direction by the drive shaft 23 of the actuator 20. A piston member 9, and a partition plate 11 having an insertion hole 15 to which the piston member 9 is inserted.

  The first mounting bracket 1 is formed in a substantially cylindrical shape from a metal material such as an aluminum alloy, and a threaded portion 1a is recessed in the upper end surface thereof because a female screw is threaded on the inner peripheral surface. In addition, an overhanging portion 1b is formed on the outer peripheral portion of the first mounting portion 1 so as to protrude radially outwardly in a substantially flange shape, and this overhanging portion 1b comes into contact with the stopper fitting 6 so that It is configured to obtain a stopper action at the time of positioning.

  The second mounting bracket 2 includes a cylindrical metal fitting 4 on which the vibration-proof base 3 is vulcanized and a bottom metal fitting 5 fixed to the lower portion of the cylindrical metal fitting 4 by caulking. The cylindrical metal fitting 4 is formed in a cylindrical shape having an opening that spreads upward, and the bottom metal fitting 5 is formed in a cup shape having a bottom portion, respectively, from a steel material or the like. In addition, the stopper metal fitting 6 which surrounds the outer peripheral side and upper surface side of the overhang | projection part 1b in the 1st attachment metal fitting 1 is being fixed to the opening peripheral edge of the cylindrical metal fitting 4 by caulking. A mounting bolt 5 a is projected from the bottom of the bottom metal fitting 5.

  The vibration isolator base 3 is formed in a truncated cone shape from a rubber-like elastic body, and is vulcanized and bonded between the lower surface side of the first mounting bracket 1 and the upper end opening of the cylindrical bracket 4. Further, a rubber film 3a covering the inner peripheral surface of the cylindrical metal fitting 4 is connected to the lower end portion of the vibration isolating base 3, and the outer peripheral edge of the partition plate 11 is in close contact with the rubber film 3a. An orifice 13 is formed between the partition plate 11 and the rubber film 3a.

  The diaphragm 7 is formed as a rubber film bent in a bellows shape from a rubber-like elastic body, and is vulcanized and bonded to an annular mounting plate 10 as viewed from above. The diaphragm 7 is attached to the second mounting bracket 2 by the mounting plate 10 being nipped and fixed to a caulking portion where the bottom metal fitting 5 is fixed by caulking under the cylindrical metal fitting 4. As a result, a liquid sealing chamber 8 is formed between the upper surface side of the diaphragm 7 and the lower surface side of the vibration isolating substrate 3. The liquid enclosure 8 is filled with an antifreeze liquid (not shown) such as ethylene glycol.

  The piston member 9 is a member formed in a cylindrical shape from a rubber-like elastic body, and is formed integrally with the diaphragm 7. A shaft-like embedded member 12 is vulcanized and bonded inside the piston member 9. The piston member 9 and the embedded member 12 are disposed in a vertical posture along the axis O of the second mounting bracket 2 (in the present embodiment, coaxially). The piston member 9 is vibrated and displaced in the direction of the axis O in the liquid sealing chamber 8 when the driving force of the actuator 20 is transmitted through the driving shaft 23. Thereby, the hydraulic pressure control of the liquid enclosure chamber 8 is performed. The embedded member 12 is a member that forms part of the drive shaft 23, and constitutes the drive shaft 23 together with a mover 22 described later.

  The partition plate 11 is formed in a disk shape from a resin material, and the partition plate 11 is disposed between the vibration isolating base 3 and the diaphragm 7, so that the liquid sealing chamber 8 is disposed on the side of the vibration isolating base 3. The chamber is divided into two chambers, a first liquid chamber 8a and a second liquid chamber 8b on the diaphragm 7 side. The piston member 9 is inserted into the insertion hole 15 (see FIG. 2) opened in the partition plate 11, and the piston member 9 defines a part of the partition wall that partitions the first liquid chamber 8a and the second liquid chamber 8b. Forming. Further, the partition plate 11 is held between the mounting plate 10 of the diaphragm 7 and the step portion formed on the film portion 3 a of the vibration-isolating base 3.

  The actuator 20 is a movable iron core electromagnet type linear actuator, is disposed on the opposite side of the liquid sealing chamber 8 with the diaphragm 7 interposed therebetween, and is sealed from the outside in a storage space formed by the bottom metal fitting 5. Stored and held.

  The actuator 20 includes a stator 21 fixed to the second mounting bracket 2, a mover 22 that is supported so as to reciprocate with respect to the stator 21, and is connected to the piston member 9 to vibrate and displace it. Is provided.

  The mover 22 is a shaft-like member disposed in a vertical position along the axis O of the second mounting bracket 2 (coaxially in the present embodiment), and its tip is embedded in the piston member 9. The movable member 22 and the embedded member 12 are integrally connected to the base 12a (see FIG. 3) of the embedded member 12 and the piston member 9 is vibrated up and down along the axis O direction (reciprocating). Move).

  As described above, the mover 22 constitutes the drive shaft 23 together with the embedded member 12. That is, the drive shaft 23 is configured to include the mover 22, the embedded member 12, and the bolt. Specifically, the mover 22 is formed in a cylindrical shape having a through-hole along the axis O, while the embedded member 12 is open to the proximal end side and is internally threaded with a female screw. The movable member 22 and the embedded member 12 are integrally connected to each other by screwing the front end of the bolt inserted from the proximal end side of the movable member 22 into the female screw portion of the embedded member 12. 23 is configured.

  On the outer peripheral surface of the mover 22, a magnetic material portion 24 is fixed as a mover iron core formed by laminating a number of metal plates made of a magnetic metal such as an electromagnetic steel plate. A plurality (two in the present embodiment) of magnetic material portions 24 are provided with a predetermined interval in the direction of the axis O. Further, the mover 22 is reciprocable in the direction of the axis O with respect to the stator 21 via a plate spring 25 that is a pair of upper and lower elastic support members, and has a position and an axis O in the direction of the axis O. Are supported in a state where their positions in the orthogonal direction are positioned.

  The stator 21 has an annular shape that surrounds the outer periphery of the mover 22 coaxially, and supports the mover 22 so that it can reciprocate in the direction of the axis O in its hollow portion. It is held in a lowered state. The attachment plate 50 is nipped and fixed together with the attachment plate 10 of the diaphragm 7 to a caulking portion where the bottom fitting 5 is fixed by caulking under the cylindrical fitting 4.

  The stator 21 has a yoke 26 formed by laminating a large number of annular metal plates made of a magnetic metal such as an electromagnetic steel plate, and a radial direction from both sides so as to face each other with the magnetic material portion 24 sandwiched in the central portion of the yoke 26. A pair of magnetic pole portions 28 projecting inward are provided.

  The tip of the magnetic pole portion 28 of the stator 21 facing the magnetic material portion 24 (that is, the inner end of the magnetic pole portion 28) is adjacent to the movable member 22 along the reciprocating direction (axis O direction). A pair of upper and lower permanent magnets 30 and 31 facing the mover 22 while being arranged side by side are orthogonal to the reciprocating direction of the mover 22 so that their magnetic poles are NS different from each other. The magnetic poles are arranged in the direction, and the arrangement of the magnetic poles (N pole and S pole) is reversed. In the present embodiment, two pairs of upper and lower permanent magnets 30 and 31 are arranged side by side in the direction of the axis O so as to correspond to the magnetic material portion 24.

  A coil 32 is wound around each of the pair of magnetic pole portions 28 of the stator 21 around an axis center in a direction orthogonal to the reciprocating direction (axis O direction) of the mover 22, and a pair of permanent magnets. The magnetic flux passing through 30 and 31 can be generated. In the present embodiment, a pair of permanent magnets 30, 31 are provided at the inner end portions of the pair of magnetic pole portions 28 of the stator 21 facing each other with the magnetic material portion 24 interposed therebetween. The permanent magnets 30 and 31 are opposed to each other with the mover 22 sandwiched in a direction orthogonal to the reciprocating direction of the mover 22, and the magnetic poles are arranged so that the opposing magnetic poles are different from each other (left and right in FIG. 1). ) In reverse.

  Thereby, when a current in the positive direction is passed through the coil 32, the direction of the magnetomotive force generated in the coil 32 and the direction of the magnetomotive force of the upper permanent magnet 30 are the same, and the magnetomotive force is increased. On the other hand, the direction of the magnetomotive force of the lower permanent magnet 31 and the direction of the magnetomotive force of the coil 32 are opposite to each other, and the magnetomotive forces of the two are canceled and weakened. As a result, an upward force acts on the magnetic material portion 24 and the mover 22 rises. On the other hand, when a current in the reverse direction is passed through the coil 32, contrary to the above, a downward force acts on the magnetic material portion 24 and the mover 22 is lowered. Therefore, the needle | mover 22 can be reciprocated up and down by switching the direction of the electric current of the coil 32 alternately forward and reverse.

  Next, the detailed configuration of the partition plate 11 will be described with reference to FIG. 2A is a top view of the partition plate 11, and FIG. 2B is a cross-sectional view of the partition plate 11 taken along the line IIb-IIb in FIG. 2A.

  The partition plate 11 is formed from a resin material in a symmetrical disk shape around the axis O, and an orifice forming portion 14 having a U-shaped cross section that is opened radially outward is formed on the outer peripheral side. . That is, the partition plate 11 has a cylindrical body that hangs down along the axis O from the lower surface of the circular plate-like body as viewed from above, and a wall portion that projects radially outward from the outer peripheral surface of the cylindrical body. As a result, the orifice forming portion 14 is formed on the outer peripheral side. In addition, the partition plate 11 is formed with a space opened downward for accommodating the diaphragm 7 and the piston member 9 on the inner peripheral side (axis O side) of the orifice forming portion 14.

  The orifice forming part 14 forms an orifice 13 having a substantially rectangular cross section by being in close contact with the rubber film 3a covering the inner periphery of the cylindrical metal fitting 4 (see FIG. 1). The orifice forming portion 14 includes a notch portion 14 a formed in a recess in the upper wall portion of the orifice forming portion 14, an opening portion 14 b formed in the body portion of the orifice forming portion 14, and the orifice forming portion 14. And a vertical wall 14c that connects the upper and lower wall portions and the body portion. The orifice 13 is divided in the circumferential direction by the vertical wall 14c, communicated with the first liquid chamber 8a through the notch 14a, and communicated with the second liquid chamber 8b through the opening 14b (FIG. 1). reference). That is, in the present embodiment, the orifice 13 is formed as an orifice channel having a channel length of about a half circumference from the notch 14a to the opening 14b.

  An insertion hole 15 having a circular shape in top view is formed through the central portion of the partition plate 11. The insertion hole 15 is formed as a hole coaxial with the axis O and having an inner diameter D1, and the piston member 9 is inserted (see FIG. 1). In this embodiment, the insertion hole 15 is provided with a draft angle (for example, 3 degrees) extending downward in FIG. 2B in order to facilitate release from the resin mold. In this case, the diameter D1 corresponds to the minimum diameter of the insertion hole 15.

  Next, the detailed configuration of the diaphragm 7 and the piston member 9 will be described with reference to FIG. 3A is a top view of the diaphragm 7 and the piston member 9, and FIG. 3B is a cross-sectional view of the diaphragm 7 and the piston member 9 taken along line IIIb-IIIb in FIG. 3A.

  As described above, the diaphragm 7 is a rubber film-like member that forms the liquid sealing chamber 8 between the vibration isolating base 3 and is bent in a bellows shape between the mounting plate 10 and the piston member 9. In this way, it is formed in a W-shape in cross-sectional view, so that the free length of the diaphragm 7 is ensured in a limited space.

  In particular, in the present embodiment, the center side of the diaphragm 7 is connected to the lower surface of the piston member 9 (the lower side surface in FIG. 3B) and extends downward along the axis O from the connecting portion with the lower surface. After that, the shape of the diaphragm 7 is formed in a shape extending obliquely upward. Therefore, as compared with the case where the center side of the diaphragm 7 is connected to the outer peripheral surface of the piston member 9, the free length of the diaphragm 7 is ensured to ensure dynamic characteristics (damping characteristics, dynamic spring constant, etc.) and the diaphragm 7. It is possible to improve the durability. Moreover, the burden in the connection part of the diaphragm 7 and piston member 9 accompanying the vibration displacement of the piston member 9 can be reduced, and the durability in the connection part can be improved.

  As described above, the piston member 9 is a member formed integrally with the diaphragm 7 from a rubber-like elastic body. The piston member 9 is formed in a columnar body coaxial with the axis O and having an outer diameter D2. It is inserted through the insertion hole 15 (see FIG. 1). The diameter D2 of the piston member 9 is slightly smaller (for example, 0.1 mm) than the diameter D1 (see FIG. 2) of the insertion hole 15 (D2 <D1). Further, the outer diameter of the piston member 9 is set to a constant size along the axis O in the present embodiment. However, the draft angle of the upper stagnation in FIG. 3B may be given to part or all along the axis O.

  It should be noted that the piston member 9 has a height dimension (dimension in the direction of the axis O) in which the piston member 9 does not fall out of the insertion hole 15 (see FIG. 2) even when the piston member 9 is displaced maximum by the actuator 20. ). This height dimension is preferably 3 to 10 times the maximum displacement amount of the piston member 9 (the absolute value of the maximum amplitude from the neutral position to one side or the other side). In the present embodiment, it is 5 times.

  As described above, the embedded member 12 is a metal shaft-like body that constitutes the drive shaft 23 together with the movable element 22 (see FIG. 1), and is connected to the piston member 9 by vulcanization adhesion. The burying member 12 includes a base portion 12a formed in a shaft shape, and a projecting portion 12b formed in a flange shape having a circular shape in a top view by projecting radially outward from the outer peripheral surface of the tip of the base portion 12a. Note that only the distal end side of the base portion 12 a is embedded in the piston member 9 together with the protruding portion 12 b, and the proximal end side protrudes from the lower surface of the piston member 9.

  Here, the diameter of the base 12a is preferably set to 15% or more and 50% or less with respect to the diameter D2 of the piston member 9. On the other hand, the diameter of the overhanging portion 12b is preferably set to 70% or more and 100% or less with respect to the diameter D2 of the piston member 9. As will be described later, it is intended to reduce the weight by securing the area for receiving the hydraulic pressure and securing the generated force, while reducing the diameter of the portion that does not affect the generated force.

  Returning to FIG. 1, a manufacturing method of the active liquid-filled vibration isolator 100 configured as described above will be described. The diaphragm 7 and the piston member 9 are integrated in a state where the first molded body in which the first mounting bracket 1 and the second mounting bracket 2 are connected by the vibration isolating base 3, and the mounting plate 10 and the embedded member 12 are vulcanized and bonded. The second molded bodies formed in the above are each vulcanized and molded by a rubber vulcanization mold.

  The first molded body, the partition plate 11 and the second molded body are submerged in the liquid, and the partition plate 11 is inserted into the cylindrical metal fitting 4 from the lower opening of the first molded body, and then the diaphragm 7 is placed over the first molded body. Assemble the assembly in liquid. When the diaphragm 7 is covered, the piston member 9 is inserted through the insertion hole 15. Next, the first assembly is taken out of the liquid in a posture in which the first mounting bracket 1 is downward, and while maintaining this posture, the actuator 20 is stacked from the lower surface side of the diaphragm 7, and the embedded member 12, the mover 22, Is fastened with bolts. And the bottom metal fitting 5 is put on the actuator 20, and the bottom metal fitting 5 is fixed to the lower opening of the cylindrical metal fitting 4 by caulking. Further, the stopper fitting 6 is fixed to the upper opening of the cylindrical fitting 4 by caulking. Thereby, the production of the active liquid-filled vibration isolator 100 is completed.

  Next, the operation of the active liquid-filled vibration isolator 100 will be described. When a relatively large amplitude low-frequency vibration is input, the liquid flows between the first liquid chamber 8a and the second liquid chamber 8b via the orifice 13 formed in the partition plate 11. The vibration can be attenuated by the liquid flow effect.

  When a relatively small amplitude high-frequency vibration is input, a sinusoidal AC voltage is applied to the coil 32 of the actuator 20 by a control unit (not shown), so that the movable element 22 (that is, embedded) The drive shaft 23) configured with the member 12 is reciprocated up and down. Thereby, the piston member 9 connected to the drive shaft 23 is vibrated and displaced in the opposite phase to the input vibration (that is, when the first mounting bracket 1 is displaced toward the partition plate 11 in the proximity direction). When the piston member 9 is displaced in a direction approaching the first mounting bracket 1 and the first mounting bracket 1 is displaced in a direction away from the partition plate 11, the piston member 9 is separated from the first mounting bracket 1. The displacement of the first liquid chamber 8a can be controlled and vibration can be reduced.

  In this case, since the piston member 9 is integrally formed with the diaphragm 7 from the rubber-like elastic body, the active liquid-filled vibration isolator 100 is like a conventional product in which the piston member 9 and the diaphragm 7 are formed as separate parts. In addition, it is not necessary to connect these two parts by caulking. Therefore, the number of assembling steps can be reduced and the product cost can be reduced. Further, since the material cost can be reduced as compared with the case where the piston member 9 is made of a resin material, the product cost can be reduced accordingly.

  On the other hand, when the piston member 9 is composed of a rubber-like elastic body, the piston member 9 is elastically deformed by the hydraulic pressure received during the vibration displacement, and a force transmission loss occurs. Therefore, the generated force due to the vibration displacement of the piston member 9 is reduced, and the hydraulic pressure control of the first liquid chamber 8a becomes insufficient. On the other hand, in this embodiment, since the embedded member 12 (drive shaft 23) made of a metal material is embedded in the piston member 9, the embedded member 12 receives the hydraulic pressure received during the vibration displacement. be able to. Therefore, since the transmission loss of force can be reduced and the generated force can be ensured, the fluid pressure control of the first fluid chamber 8a can be reliably performed.

  Further, the embedded member 12 embedded in the piston member 9 has a shape in which a base portion 12a is formed in an axial shape, and an overhanging portion 12b protruding outward in the radial direction is disposed at the axial end of the base portion 12a. While reducing the weight, it is possible to improve the generated force due to the vibration displacement of the piston member 9. That is, the overhanging portion 12b is formed at the tip of the base portion 12a in the axial direction, and the embedded member 12 has a T-shaped cross section, so that an area of a portion necessary for receiving the hydraulic pressure is ensured, and the force transmission loss By reducing the remaining portion (base portion 12a) of the embedded member 12 that is not the portion that receives the hydraulic pressure, the weight can be reduced without affecting the generation of force transmission loss. .

  Next, a second embodiment will be described with reference to FIGS. In the first embodiment, the case where the unevenness (rib) is not formed on the outer peripheral surface of the piston member 9 has been described. However, in the piston member 209 of the second embodiment, the rib-shaped rib 291 protrudes on the outer peripheral surface. Established. In addition, the same code | symbol is attached | subjected to the part same as 1st Embodiment mentioned above, and the description is abbreviate | omitted.

  FIG. 4 is a partially enlarged cross-sectional view of an active liquid-filled vibration isolator 200 according to the second embodiment, and corresponds to FIG. FIG. 4 illustrates a state before the engine is supported (that is, a state before the weight of the engine is loaded).

  As shown in FIG. 4, in the vibration isolator 200 in the second embodiment, a liquid sealing chamber 8 is formed between the vibration isolator base 3 and the diaphragm 7 as in the case of the first embodiment. The liquid enclosure chamber 8 is partitioned into a first liquid chamber 8a and a second liquid chamber 8b by a partition plate 211. Further, the embedded member 12 is reciprocated up and down by the actuator 20 (see FIG. 1), so that the piston member 209 is subjected to vibration displacement in an opposite phase with respect to the input vibration, whereby the first liquid chamber 8a is displaced. The hydraulic pressure is controlled and vibration is reduced.

  Next, a detailed configuration of the partition plate 211 in the second embodiment will be described with reference to FIG. Fig.5 (a) is a top view of the partition plate 211, FIG.5 (b) is sectional drawing of the partition plate 211 in the Vb-Vb line | wire of Fig.5 (a). The partition plate 211 in the second embodiment has the same configuration as that of the partition plate 11 (see FIG. 2) in the first embodiment except that the partition plate 211 includes a cylindrical portion 216 that forms the insertion hole 215. .

  As shown in FIG. 5, a cylindrical portion 216 formed in a cylindrical shape is disposed in a vertical position along the axis O (in the present embodiment, coaxially) at the center portion of the partition plate 211. The cylindrical portion 216 is formed to have an inner periphery with a circular cross section, and the inner peripheral side of the cylindrical portion 216 is an insertion hole 215. The insertion hole 215 has an inner diameter of a diameter D3, and a rib 291 of the piston member 209 is in contact with the insertion hole 215 as described later.

  As in the case of the first embodiment, the insertion hole 215 is provided with a draft angle (for example, 3 degrees) in FIG. In this case, the diameter D3 corresponds to the minimum diameter of the insertion hole 215.

  The height dimension of the cylindrical portion 216 (the dimension in the direction of the axis O) is the maximum displacement of the piston member 209 toward the vibration isolation base 3 (see FIG. 7A) and the piston member 209 toward the actuator 20 side. In either case of maximum displacement (see FIG. 7B), the overhanging portion 12b (see FIG. 6) of the embedded member 12 is positioned in the insertion hole 215 (that is, the cylinder portion 216 is stretched). The dimensions are set such that the protruding portion 12b is enclosed from the outer peripheral side.

  Thereby, the generated force accompanying the reciprocating displacement of the piston member 209 can be efficiently transmitted to the first mounting bracket 1 (see FIG. 1) using the cylindrical shape of the cylindrical portion 216. Further, the overhanging portion 12b located in the cylindrical portion 216 serves as a lid for closing the insertion hole 215 of the cylindrical portion 216, so that the outer peripheral surface of the piston member 209 and the inner peripheral surface of the cylindrical portion 216 are It is possible to easily prevent the hydraulic pressure from escaping.

  Next, a detailed configuration of the piston member 209 according to the second embodiment will be described with reference to FIG. 6A is a top view of the diaphragm 7 and the piston member 209, and FIG. 6B is a cross-sectional view of the diaphragm 7 and the piston member 209 along the line VIb-VIb in FIG. 6A. In FIG. 6, the rib 291 is schematically enlarged and illustrated for easy understanding.

  The piston member 209 in the second embodiment has the same configuration as the piston member 9 (see FIG. 3) in the first embodiment, except that a rib 291 is provided. The rib 291 is a part for suppressing hydraulic pressure from escaping from between the piston member 209 and the insertion hole 215, and protrudes from the outer peripheral surface of the piston member 209, and is circumferential in the outer peripheral surface of the piston member 209. It is formed as a ring-shaped ridge that extends continuously for one round.

  The cross-sectional shape of the rib 291 is formed in a tapered shape (in this embodiment, a semicircular shape) whose width narrows toward the projecting tip, and this cross-sectional shape is the same at any position in the circumferential direction. is there. As a result, the area of the protruding tip of the rib 291 abutting against the insertion hole 215 can be suppressed, and the protruding tip of the rib 291 can be easily deformed, so that the escape of hydraulic pressure is suppressed and the sliding resistance is reduced. This can be reduced to improve the generated force.

  The rib 291 is formed at a position that is lower (diaphragm 7 side) than a position where the protruding portion 12b of the embedded member 12 is extended radially outward, that is, a position corresponding to the base portion 12a. Thereby, since the thickness dimension (dimension in the left-right direction in FIG. 6B) of the rubber-like elastic body of the piston member 209 that supports the rib 291 can be increased, the deformability of the rib 291 can be ensured accordingly. Therefore, it is possible to reduce the sliding resistance and improve the durability of the rib 291 while suppressing the escape of the hydraulic pressure.

  Since the rib 291 is integrally formed with the piston member 209 from a rubber-like elastic body, the product cost can be reduced and the durability can be improved. That is, in the manufacturing process of the active liquid-filled vibration isolator 200, the rib 291 can be formed simultaneously with the diaphragm 7 and the piston member 209 during the vulcanization molding, so the rib 291 is prepared as a separate part. In addition, there is no need to fix the rib 291 to the outer peripheral surface of the piston member 209 by bonding or the like. Therefore, the number of parts and the number of assembling steps can be reduced, the product cost can be reduced, and the fixation between the piston member 209 and the rib 291 can be strengthened to improve the durability (suppressing the dropping of the rib 291). Can do.

  Here, the outer diameter of the rib 291 in the top view (viewed in the direction of the axis O) is the diameter D4. In this case, the diameter D3 (see FIG. 5) of the insertion hole 215 is larger than the diameter D2 of the piston member 209 and slightly smaller (for example, 0.05 mm) than the diameter D4 of the rib 291 (D2 < D3 <D4). Accordingly, when the piston member 209 is inserted into the insertion hole 215, the rib 291 is brought into contact with the inner peripheral surface of the insertion hole 215 in a compressed state.

  Note that the protruding height of the rib 291 is such that the protruding tip of the insertion hole 215 is at the protruding tip even when the piston member 209 is displaced in the maximum direction (see FIGS. 7A and 7B). The dimension is set in consideration of the draft angle of the insertion hole 215 so that the state in contact with the inner peripheral surface is maintained. Similarly, the projecting position of the rib 291 (axial center O direction position) is the maximum displacement of the piston member 209 in any direction (see FIGS. 7A and 7B). In order to maintain a state in which the protruding tip is in contact with the inner peripheral surface of the insertion hole 215, the protrusion 20 is disposed at a position in consideration of the maximum displacement amount in the vertical direction by the actuator 20.

  Returning to FIG. Note that the manufacturing method of the active liquid-filled vibration isolator 200 according to the second embodiment is the same as that of the active liquid-filled vibration isolator 100 according to the first embodiment, and a description thereof will be omitted.

  As shown in FIG. 4, the height dimension (axial center O direction dimension) of the cylindrical portion 216 is set to be approximately the same as the height dimension of the piston member 209, and the piston member 209 is in the neutral position (that is, In a state where the actuator 20 is not driven), the piston member 209 and the cylindrical portion 216 are disposed at positions where their inner and outer peripheral surfaces are substantially opposed to each other. As a result, the flow resistance when the liquid flows through the flow path formed between the outer peripheral surface of the piston member 209 and the inner peripheral surface of the cylindrical portion 216 is increased, and the liquid passes over the rib 291 through the flow path. Can be suppressed. As a result, when a relatively large amplitude low frequency vibration is input, the liquid is circulated between the first liquid chamber 8a and the second liquid chamber 8b via the orifice 13 formed in the partition plate 211. (See FIG. 1), vibration attenuation due to the liquid flow effect can be more reliably exhibited.

  Next, the operation of the active liquid-filled vibration isolator 200 will be described with reference to FIG. FIG. 7A is a partially enlarged cross-sectional view of the active liquid-filled vibration isolator 200 in a state where the piston member 209 is maximum displaced upward, and FIG. 7B is a diagram in which the piston member 209 is maximum downward. It is a partial expanded sectional view of the active liquid enclosure type vibration isolator 200 in the displaced state. In FIG. 7, the displacement amount of the piston member 209 is shown larger than the actual amount. FIG. 7 shows a state before the engine is supported (that is, a state before the weight of the engine is loaded).

  When a relatively small amplitude high frequency vibration is input, a sine wave AC voltage is applied to the coil 32 of the actuator 20 by the load and control unit (not shown) as in the case of the first embodiment. The mover 22 (drive shaft 23) is reciprocated up and down (see FIG. 1), and the piston member 9 is displaced by excitation in an opposite phase to the input vibration.

  That is, when the first mounting bracket 1 (see FIG. 1) is displaced toward the partition plate 211 by vibration input, the piston member 209 is moved to the first mounting bracket as shown in FIG. When the first mounting bracket 1 is displaced in a direction away from the partition plate 211, the piston member 209 is separated from the first mounting bracket 1 as shown in FIG. Displaced in the direction. As a result, the fluid pressure in the first fluid chamber 8a can be controlled and vibrations can be reduced.

  In this case, since the rib 291 is provided on the outer peripheral surface of the piston member 209 and the protruding tip of the rib 291 is in contact with the inner peripheral surface of the insertion hole 215, the outer peripheral surface of the piston member 209 and the insertion hole 215 It is possible to suppress the escape of the hydraulic pressure from the gap between the inner peripheral surface and improve the generated force due to the vibration displacement of the piston member 209.

  Further, as described above, the rib 291 that is in contact with the inner peripheral surface of the insertion hole 215 is provided on the outer peripheral surface of the piston member 209, so that the positioning of the piston member 209 with respect to the insertion hole 215 (the position at which the axis O coincides). Can be performed, so that the assembling work can be simplified. For example, when a predetermined gap is provided between the piston member 9 and the insertion hole 15 as in the case of the first embodiment, the piston member is set so that the gap is uniform in the circumferential direction. 9 is required to assemble 9 into the insertion hole 15 and connect the piston member 9 and the actuator 20, which complicates the operation. On the other hand, in the second embodiment, if the piston member 209 is inserted through the insertion hole 215, the rib 291 abuts against the inner peripheral surface of the insertion hole 215, so that the piston member 209 is in contact with the insertion hole 215. Since positioning (centering) can be performed, the assembly of the piston member 209 into the insertion hole 215 and the operation of connecting the piston member 209 and the actuator 20 can be facilitated.

  Furthermore, since the rib 291 is made of a rubber-like elastic body, even if the piston member 209 is assembled at a position that is off-axis with respect to the insertion hole 215, the off-axis is absorbed by elastic deformation of the rib 291. At the same time, since the rib 291 is compatible, it is possible to suppress the formation of a gap between the outer peripheral surface of the piston member 209 and the inner peripheral surface of the insertion hole 215. Therefore, it is possible to prevent the hydraulic pressure from escaping from the gap and to secure the generated force.

  Further, when the rib 291 is not provided, when the outer peripheral surface of the piston member 209 comes into contact with the insertion hole 215 due to the shaft misalignment, a large driving force is required to reciprocate the piston member 209. According to the embodiment, even if the piston member 209 is assembled to the insertion hole 215 in an off-axis state, the piston 209 can be reciprocally displaced with a relatively small driving force by adapting the rib 291. Can do.

  The present invention has been described above based on the embodiments. However, the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. It can be easily guessed.

  The numerical values given in the above embodiments are merely examples, and other numerical values can naturally be adopted. For example, in the second embodiment, the case where one rib 291 is provided on the outer peripheral surface of the piston member 209 has been described. However, the present invention is not limited to this, and two or more ribs may be provided.

  In each of the above embodiments, the case where the partition plates 11 and 211 are formed from a resin material has been described. However, the present invention is not necessarily limited to this, and it is naturally possible to form the partition plates from other materials. Examples of other materials include steel materials and aluminum alloys.

  In the second embodiment, the case where the rib 291 is formed in a ring shape continuous in the circumferential direction of the piston member 209 has been described. However, the present invention is not limited to this, and the rib 291 is formed on the outer peripheral surface of the piston member 209. It may be provided in a spiral shape.

  In the second embodiment, the case where the outer diameter D4 of the rib 291 is larger than the inner diameter D3 of the insertion hole 215 has been described. However, the present invention is not necessarily limited to this, and the outer diameter D4 of the rib 291 is inserted into the insertion hole. The same dimension as the inner diameter D3 of 215 may be set (D3 = D4), or the outer diameter D4 of the rib 291 may be set smaller than the inner diameter D3 of the insertion hole 215 (D4 <D3). .

  When the outer diameter D4 of the rib 291 is set to the same dimension as the inner diameter D3 of the insertion hole 215 (D3 = D4), the driving is performed by reducing the frictional resistance generated between the inner diameter of the insertion hole 215. It is possible to suppress the hydraulic pressure from escaping from the gap between the outer peripheral surface of the piston member 209 and the inner peripheral surface of the insertion hole 215 while suppressing loss. Therefore, it is possible to efficiently improve the generated force due to the vibration displacement of the piston member 209.

  In the second embodiment, the case where the rubber-like elastic body is covered on the upper surface side of the overhanging portion 12b of the embedded member 12 has been described. However, the present invention is not necessarily limited to this, and the upper surface of the overhanging portion 12b. The piston member 209 may be vulcanized with the side exposed. In this case, since the rubber-like elastic body covered on the upper surface side of the overhanging portion 12b can be prevented from elastically deforming due to the hydraulic pressure received during the vibration displacement, the transmission loss of the force is reduced accordingly. Generating power can be secured.

100,200 Active liquid-filled vibration isolator 1 First mounting bracket (first mounting bracket)
2 Second mounting bracket (second mounting bracket)
3 Anti-vibration base 4 Cylindrical bracket (part of second fixture)
5 Bottom bracket (part of second fixture)
7 Diaphragm 8 Liquid enclosure chamber 8a First liquid chamber 8b Second liquid chamber 9,209 Piston members 11, 211 Partition plate (partition member)
12 Embedded member (part of drive shaft)
12a Base portion 12b Overhang portion 13 Orifices 15, 215 Insertion hole 20 Actuator 22 Movable element (part of drive shaft)
23 Drive shaft 291 Rib

Claims (4)

A first mounting tool, a second mounting tool, a vibration isolating base that connects the second mounting tool and the first mounting tool and is made of a rubber-like elastic body, and is attached to the second mounting tool. A liquid sealing chamber is formed between the anti-vibration base and a diaphragm made of a rubber-like elastic body, a drive shaft connected to the diaphragm and formed of a metal material, and the liquid sealed with the diaphragm interposed therebetween. An actuator disposed on the opposite side of the chamber; a piston member that is vibrated and displaced in the axial direction by a drive shaft of the actuator; and a piston that has an insertion hole through which the piston member is inserted and is inserted into the insertion hole A partition member that divides the liquid sealing chamber into a first liquid chamber on the vibration-isolating base side and a second liquid chamber on the diaphragm side together with a member, and an orifice that communicates the first liquid chamber and the second liquid chamber. When, in the active liquid-filled vibration damping device provided with,
The piston member is formed integrally with the diaphragm from a rubber-like elastic body,
An active liquid-filled vibration isolator, wherein the drive shaft is embedded in the piston member.   The drive shaft includes a shaft-shaped base portion and a flange-shaped projecting portion that projects radially outward at an axial tip of the base portion, and includes at least a part of the base portion and the projecting portion. The active liquid-filled vibration isolator according to claim 1, wherein a part is embedded in the piston member.   3. The active liquid sealing according to claim 1, further comprising a rib projecting from an outer peripheral surface of the piston member and extending in a circumferential direction of the piston member and configured by a rubber-like elastic body. Type vibration isolator.   4. The active liquid-filled vibration isolator according to claim 3, wherein the rib is formed integrally with the piston member.

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